My advice - BE CAREFUL
Investment and trading books, articles and videos are made by people who might not actually be winning traders. They make their money by writing "investment materials" and sell it to us, the plebs.
Plus "as traders", most of you will lose money and leave. Some of you might return and lose more money. Some might have learned their lesson the hard way and just HODL Bitcoin. The few who actually put in the most time, effort and who are well-capitalized might make it.
In some point yes it is, but in other way is people want to read these because they want to know what are the other strategies and their experiences with the trading practices its not all about buying the book its all about too base on the studies they made, and most of the important is the experience. Like you are paying a service. Are you willing to pay a person who does not know the things you want to know? of course not in some point that's the perspective of the use with the book.